;;
  ;;  spreadspace pic utils
  ;;
  ;;
  ;;  Copyright (C) 2011 Christian Pointner <equinox@spreadspace.org>
  ;;
  ;;  This file is part of spreadspace pic utils.
  ;;
  ;;  spreadspace pic utils is free software: you can redistribute it and/or modify
  ;;  it under the terms of the GNU General Public License as published by
  ;;  the Free Software Foundation, either version 3 of the License, or
  ;;  any later version.
  ;;
  ;;  spreadspace pic utils is distributed in the hope that it will be useful,
  ;;  but WITHOUT ANY WARRANTY; without even the implied warranty of
  ;;  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  ;;  GNU General Public License for more details.
  ;;
  ;;  You should have received a copy of the GNU General Public License
  ;;  along with spreadspace pic utils. If not, see <http://www.gnu.org/licenses/>.
  ;;

  ;; flash read --------
cmd_reset
  movlw     E_OK
  call      ack_cmd
  movlb     .3
cmd_resset_wait_ack
  btfss     TXSTA,TRMT
  goto      cmd_resset_wait_ack
  reset

  ;; flash read --------
cmd_r_flash
;;   movlw     FSS                 ; initialize EEADR:EEADRH and FSR
;;   movwf     cnt
;;   movlw     b'01011000'
;;   movwf     STATUS
;;   movlw     combuff + .2
;;   movwf     FSR
;;   movf      INDF,w
;;   movwf     EEADR
;;   incf      FSR,f
;;   movf      INDF,w
;;   movwf     EEADRH
;; read_flash_segment_loop
;;   bsf       STATUS,RP0          ; perform the actual read
;;   bsf       EECON1,EEPGD
;;   bsf       EECON1,RD
;;   nop
;;   nop
;;   bcf       STATUS,RP0
;;   movf      EEDAT,w             ; load code word from EEDAT:EEDATH to combuff
;;   movwf     INDF
;;   incf      FSR,f
;;   movf      EEDATH,w
;;   movwf     INDF
;;   incf      FSR,f
;;   incfsz    EEADR,f             ; increment flash address
;;   goto      read_flash_segment_next
;;   incf      EEADRH,f
g;; read_flash_segment_next
;;   decfsz    cnt,f
;;   goto      read_flash_segment_loop
;;   bcf       STATUS,RP1
;;   clrf      combuff + .2  ; = E_OK
;;   movlw     .1 + .2*FSS   ; bytes to send
;;   call      send_answer
  movlw     E_NOT_IMPL
  call      ack_cmd
  goto      wait_new_cmd

  ;; flash write --------
cmd_w_flash
;;   movf      combuff + .3,f      ; if addr[15:8] == 0 -> boot loader section
;;   btfsc     STATUS,Z
;;   goto      address_prohibited
;;   movlw     FLASH_BOUNDARY      ; addr on boundary?
;;   andwf     combuff + .2,w
;;   btfss     STATUS,Z
;;   goto      address_invalid
;;   movlw     FSS                 ; initialize EEADR:EEADRH and FSR
;;   movwf     cnt
;;   movlw     b'01011000'
;;   movwf     STATUS
;;   movlw     combuff + .2
;;   movwf     FSR
;;   movf      INDF,w
;;   movwf     EEADR
;;   incf      FSR,f
;;   movf      INDF,w
;;   movwf     EEADRH

;; write_flash_segment_loop
;;   incf      FSR,f               ; load code word into EEDAT:EEDATH
;;   movf      INDF,w
;;   movwf     EEDAT
;;   incf      FSR,f
;;   movf      INDF,w
;;   movwf     EEDATH

;;   bsf       STATUS,RP0          ; now start the acutal write sequence
;;   bsf       EECON1,EEPGD
;;   bsf       EECON1,WREN
;;   movlw     H'55'
;;   movwf     EECON2
;;   movlw     H'AA'
;;   movwf     EECON2
;;   bsf       EECON1,WR
;;   nop
;;   nop
;;   bcf       EECON1,WREN
;;   bcf       STATUS,RP0
;;   incfsz    EEADR,f             ; increment flash address
;;   goto      write_flash_segment_next
;;   incf      EEADRH,f
;; write_flash_segment_next
;;   decfsz    cnt,f
;;   goto      write_flash_segment_loop
;;   bsf       STATUS,RP0
;;   clrw                          ; check if a write error occured
;;   btfsc     EECON1,WRERR
;;   movlw     E_FLASH_WERR
;;   bcf       STATUS,RP1
;;   bcf       STATUS,RP0
;;   movwf     combuff + .2  ; = E_OK
;;   movlw     .1            ; bytes to send
;;   call      send_answer
  movlw     E_NOT_IMPL
  call      ack_cmd
  goto      wait_new_cmd